Turning is the use of the workpiece in the lathe relative to the tool rotation of the workpiece cutting method. The cutting energy of the turning is mainly provided by the workpiece rather than the tool. Turning is the most basic and most common method of cutting, in the production occupies a very important position. Turning is suitable for processing the rotating surface, most of the workpiece with a rotating surface can be machined with turning methods, such as inside and outside the cylindrical surface, inside and outside the conical surface, face, groove, thread and rotary forming surface, the tool is mainly used.
